Composite scaffold for the repair, reconstruction, and regeneration of soft tissues
A composite scaffold having a highly porous interior with increased surface area and void volume is surrounded by a flexible support structure that substantially maintains its three-dimensional shape under tension and provides mechanical reinforcement during repair or reconstruction of soft tissue while simultaneously facilitating regeneration of functional tissue.
1. A composite scaffold comprising:
a microporous matrix having a multitude of interconnected pores opening to an exterior surface of the microporous matrix and collectively defining an interior void space; and
a structure supporting the microporous matrix comprising first and second outer layers separated by the interior void space, and a plurality of spacer elements yarns extending through the interior void space and connecting the first and second outer layers;
the composite scaffold having a substantially rectangular cross-section defined by exterior sides, and
wherein a plurality of the interconnected pores proximate one of the exterior sides have a largest dimension oriented relative to the one exterior side.
2. The composite scaffold of claim 1 wherein at least approximately 60% of the void space comprises pores having a size dimension of at least 10 μm or greater.
3. The composite scaffold of claim 1 wherein a volume of the void space is between approximately 3.0 cm 3 /gram and 9.0 cm 3 /gram.
4. The composite scaffold of claim 1 wherein the composite scaffold has a cross sectional area of approximately between 3 mm 2 and 250 mm 2 , and
wherein the cross-sectional area changes less than approximately 17% at a strain percentage of 13%.
5. The composite scaffold of claim 1 wherein a surface area of the composite scaffold is between approximately 0.3 m 2 /gram and 1.5 m 2 /gram.
6. The composite scaffold of claim 1 wherein the plurality of the interconnected pores have a largest dimension oriented between approximately between 45° and 135° relative to the one exterior side.
7. The composite scaffold of claim 1 wherein the plurality of the interconnected pores have a largest dimension oriented between approximately between 60° and 120° relative to the one exterior side.
8. The composite scaffold of claim 1 wherein the plurality of the interconnected pores have a largest dimension oriented between approximately between 75° and 105° relative to the one exterior side.
9. The composite scaffold of claim 1 wherein the composite scaffold has an ultimate stress of approximately between 2.5 MPa and 30 MPa.
10. The composite scaffold of claim 1 wherein the composite scaffold has a yield stress of approximately between 2.5 MPa and 30 MPa.
11. The composite scaffold of claim 1 wherein the composite scaffold has a modulus of approximately between 2.5 MPa and 70 MPa, wherein modulus is calculated using a cross-sectional area of material comprising the composite scaffold and the void space.
12. The composite scaffold of claim 1 wherein the composite scaffold has a modulus of approximately between 150 MPa and 600 MPa, wherein modulus is calculated using a cross-sectional area of only material comprising the composite scaffold.
13. The composite scaffold of claim 1 wherein the structure supporting the microporous matrix comprises a three-dimensional textile structure.
14. The composite scaffold of claim 1 wherein the microporous matrix comprises any of a sponge, foam, or textured fibers or yarns, or any combination thereof.
15. The composite scaffold of claim 1 wherein the microporous matrix comprises any of a freeze-dried sponge, open cell extrusion foam, particulate leached sponge, or any combination thereof.
16. The composite scaffold of claim 1 wherein the microporous matrix comprises any of a sponge, foam, or textured fibers or yarns, or any combination thereof disposed within the scaffold by any of knitting, weaving, lyophilization, particulate leaching, open cell extrusion, solvent casting, solid-state foaming, and cross-linking.
17. The composite scaffold of claim 1 wherein the microporous matrix comprises one of collagen and hydrogel.
18. The composite scaffold of claim 1 wherein the scaffold comprises monofilament, multifilament, or textured yarns, or any combination thereof, knitted into a three-dimensional structure.
19. The composite scaffold of claim 1 wherein the scaffold comprises any combination of synthetic bioresorbable polymers, natural polymers and/or additives.
20. The composite scaffold of claim 1 wherein the scaffold comprises any of homopolymers, copolymers, or polymer blends of any of the following:
polylactic acid, polyglycolic acid, polycaprolactone, polydioxanone, polyhydroxyalkanoates, polyanhydrides, poly(ortho esters), polyphosphazenes, poly (amino acids), polyalkylcyanoacrylates, poly(propylene fumarate, trimethylene carbonate, poly(glycerol sebacate), poly(glyconate), poly(ethylene glycol), poly(vinyl alcohol) and polyurethane, or any combination thereof.
21. The composite scaffold of claim 1 wherein at least approximately 70% of the void space comprises pores having a size dimension of 10 μm or greater.
22. The composite scaffold of claim 1 wherein at least approximately 80% of the void space comprises pores having a size dimension of 10 μm or greater.
23. The composite scaffold of claim 1 wherein the composite scaffold has a stiffness of approximately between 2.5 N/mm and 25 N/mm.
24. The composite scaffold of claim 1 wherein the composite scaffold has an ultimate load of approximately between 20% and 70%.
25. The composite scaffold of claim 1 wherein the composite scaffold has an ultimate load approximately between 100 N and 200 N.
26. The composite scaffold of claim 1 wherein a surface area of the composite scaffold is between approximately 0.3 m 2 /gram and 15.0 m 2 /gram.
27. The composite scaffold of claim 1 wherein a surface area of the composite scaffold is between approximately 0.6 m 2 /gram and 1.2 m 2 /gram.
28. The composite scaffold of claim 1 wherein a surface area of the composite scaffold is between approximately 0.7 m 2 /gram and 1.0 m 2 /gram.
29. The composite scaffold of claim 1 wherein the microporous matrix comprises a multitude of interconnected pores having a median pore size of between approximately 10 μm to 100 μm.
30. The composite scaffold of claim 1 wherein the microporous matrix comprises a multitude of interconnected pores having a median pore size of between approximately 12 μm to 70 μm.
31. The composite scaffold of claim 1 wherein the microporous matrix comprises a multitude of interconnected pores having a median pore size of between approximately 20 μm to 40 μm.